1. Field of the Invention
The present invention relates to an artificial retinal prosthesis system, an optical device and a retina chip, particularly to an artificial retinal prosthesis system, an extraocular optical device and an intraocular retina chip, which use an optical modulation method to convert image information into optical pulse signals.
2. Description of the Prior Art
Retinitis pigmentosa and age-related macular degradation (AMD) are diseases caused by degradation of retinal photoreceptor cells. AMD is likely to occur in aged persons. Statistic data shows that 0.8% adults aged over 40 suffer AMD and risk blindness in USA. The patients blinded by the abovementioned diseases are hard to treat with drugs. However, the researches about replacing photoreceptor cells with an artificial retina have brought much hope to the related patients.
The conventional artificial retina is powered by a solar chip and uses electricity to stimulate the residual nerve cells and generate vision. However, the related technologies normally suffer from a problem that solar chips are hard to provide sufficient power. A U.S. patent No. US20050090875 disclosed a head-wearable background light projector, which projects intense light to the intraocular retina chip to make the photocells output more power. However, the prior art decreases image contrast and degrades image quality. A Taiwan patent No. TW201334768 uses a background light eliminator to overcome the problem that the background light decreases contrast. However, the prior art needs a high-precision focusing system because the intraocular retina chip is very small. Besides, imaging light is not allowed to project to the background light eliminator. Otherwise, the signal light would be eliminated, and the image quality would be degraded. Therefore, an artificial retina technology is required to overcome the abovementioned problems.